This invention relates generally to the field of nuclear medicine, and more particularly to an improved device for removing a radioactive gas (Xenon) from a hypodermic type vial to be conducted to a gas delivery unit of known type used for conducting regional ventilation studies upon a patient. Such studies are well-known in the medical art, and a description of the same is outside the scope of the present disclosure.
In performing such studies, it is common to use individual doses of Xenon gas for each patient, which are supplied to a disposable mouthpiece section forming part of the Xenon delivery unit. The quantity of gas required for an individual study is relatively small, and is most conveniently packed in a small glass vial under relatively low pressure, the vial being sealed by a hypodermic type synthetic rubber membrane. The gas can be removed using a conventional hypodermic needle, and transferred to a breathing bag forming part of the delivery unit, or directly to the face mask used by the patient. This technique has not proved to be entirely satisfactory, for the reason that hypodermic needles are essentially designed to accommodate liquids rather than gases, and are subject to leakage. Further, unless a shield is used, the radioactive gas in the hypodermic syringe subjects the technician to repeated exposure. It is also known in the art to use a rubber bulb type device for injecting air into the vial to force the contents outwardly thereof, but this is essentially a hand operation, requiring repeated impulses to the rubber bulb, and, again, its use has not been entirely satisfactory.